# A degree preserving delta wye transformation with applications to 6-regular graphs and Feynman periods

@inproceedings{Jeffries2021ADP, title={A degree preserving delta wye transformation with applications to 6-regular graphs and Feynman periods}, author={Shannon N. Jeffries and Karen A. Yeats}, year={2021} }

We investigate a degree preserving variant of the ∆-Y transformation which replaces a triangle with a new 6-valent vertex which has double edges to the vertices that had been in the triangle. This operation is relevant for understanding scalar Feynman integrals in 6 dimensions. We study the structure of equivalence classes under this operation and its inverse, with particular attention to when the equivalence classes are finite, when they contain simple 6-regular graphs, and when they contain…

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